When someone wants to measure distances and tunnel radius, he has to set up scaffolding and use measuring tape. This kind of work takes many time and needs money and workers.
[Photocalc+] drastically reduces such resources and increase efficiency.

System configuration

iWitnessPRO software
PhotoCalc TwoView software
Off-the-shelf digital camera

Measurement procedure

Take multiple images

Import images into iWitnessPRO and calculate camera station automatically.

Input a known length within images. When you do not have such length due to long distance to the object and etc, you can input a length from camera station to a point in an image. This length can be obtained by using laser rangefinders.

Import two images into TwoView and get 3d coordinates by clicking the point which you need the 3d coordinates of.
You can also measure 3d distance and tunnel radius.